Scientists in the search for a cure for ageing; a long road ahead

​​Human beings have long chased the desire for eternal youth. But the science and study of ageing and longevity are yet to break any major grounds. The newest scheme is to hack the ageing process itself by reprogramming old cells to a younger state.

To put things into perspective, between 1900 and 2020, human life expectancy more than doubled, to 73.4 years. But this remarkable gain has come at a cost: a staggering rise in chronic and degenerative illnesses, added the National Geographic report.

But ageing remains the biggest risk factor for cancer, heart disease, Alzheimer's, Type 2 diabetes, arthritis, lung disease, and just about every other major illness. 

The efforts to find a cure for ageing are powered by artificial intelligence, big data, cellular reprogramming, and an increasingly exquisite understanding of the zillions of molecules that keep our bodies humming. 

A widely prescribed medicine to prevent organ rejection after a transplant, Rapamycin, increases the life expectancy of middle-aged mice by as much as 60%, ushering hope among scientists looking for a cure for ageing. 

Drugs called senolytics help geriatric mice stay sprightly long after their peers have died, wrote National Geographic in a recent report.

Also, diabetes drugs – "metformin and acarbose" – extreme calorie restriction, and, by one biotech investor's count, about 90 other interventions keep mice skittering around lab cages well past their usual expiration date.

American molecular biologist Cynthia Kenyon had trouble recruiting young researchers to assist her in the experiments that would break the field open 30 years ago. 

Working back then at the University of California, San Francisco, she altered one gene in tiny roundworms known as C. elegans and doubled their life span. 

The mutants acted younger, too, slithering friskily under the microscope while their unaltered peers lay about like lumps. Kenyon's discovery showed that ageing was malleable – controlled by genes, cellular pathways, and biochemical signals. 

"The whole thing shifted from being out there in the nebulous world to familiar science that everyone understood," she told National Geographic. "And everyone could do it. So people just moved in."

However, delaying death in worms and mice does not mean it will work in humans. For a brief moment, senolytics, which kill damaging cells that accumulate with age, appeared to become the first anti-ageing therapy to get regulatory approval. 

But one of the first clinical trials, a highly anticipated study of an osteoarthritis treatment, found that it did not reduce swelling or joint pain any better than a placebo.

Now researchers and biotech companies are testing senolytics to treat early-onset Alzheimer's, long Covid, chronic kidney disease, frailty in cancer survivors, and a complication of diabetes that can cause blindness. 

Clinical trials of other anti-ageing compounds are also underway but so far, none of the experimental drugs that can substantially help fight ageing, just the way it did with mice, have made it to the market.